The present invention relates generally to roof arrangements and fasteners and more particularly to a roof arrangement including a metal deck and a particular fastener which is especially suitable for use with roof arrangements including metal decks.
A typical roof structure includes a deck and a protective deck covering. Where the roof structure is sloped, for example residential use, the protective roof covering is generally comprised of roof shingles. On the other hand, where the roof structure is relatively horizontal which is for example typical in industrial structures, the protective covering generally includes roof insulation in sheet form located directly over the deck and a built-up roof over the insulation.
When insulation in sheet material form is used and when the deck is constructed of wood, it is quite easy to fasten the insulation to the deck. This is typically accomplished by means of nails. However, where the deck is constructed of metal, which is often the case, standard nails have not been found to be acceptable. One reason for this is that the nails once driven through the metal deck do not reliably remain in place and hence do not securely hold down the roof insulation. Applicant has found that to provide the metal nails with serrations does not correct this problem since the openings in the deck will generally be as large in cross-section as or slightly larger than that of the serration and hence the nail holding capability is not substantially improved. In addition, whether the metal nails or smooth or serrated, these nails do not adequately liquid seal the openings in the deck through which they are ultimately positioned. This is primarily because of the metal to metal contact between the nails and the deck and because the nail openings are often slightly larger than the nails. Further, because of the manner in which the openings have been made, i.e., by the driving force of the nails themselves, they do not generally conform to the shape of the nails.
In view of the difficulties just discussed, sheet insulation has heretofore been typically fastened to metal decks by means of screws. It should be quite apparent that this is extremely time consuming and, as a result, expensive compared to the use of nails which can be rapidly and easily driven through the sheets of insulation and into the underlying metal deck. As will be seen hereinafter, a fastener constructed in accordance with the present invention is disclosed. This fastener, like nails, can be driven through the sheets of insulation and into the deck by means of a hammer blow, thus eliminating the use of screws. In addition, the fastener disclosed herein does not have the drawback of a standard metal nail or even a serrated metal nail, which drawbacks have been discussed above.